+typedef struct msg_task *msg_task_t;
+
+/* ******************************** Hypervisor ************************************* */
+typedef struct msg_hypervisor *msg_hypervisor_t;
+
+typedef struct msg_hypervisor {
+ const char *name;
+ s_xbt_swag_hookup_t all_hypervisor_hookup;
+ xbt_dynar_t vms; // vms on this hypervisor
+ msg_host_t host; // physical host of this hypervisor
+
+/* The hypervisor object does not have parameters like the number of CPU
+* cores and the size of memory. These parameters come from those of the
+* physical host.
+**/
+ int overcommit;
+
+} s_msg_hypervisor_t;
+
+/* ******************************** VM ************************************* */
+typedef msg_host_t msg_vm_t;
+typedef msg_host_priv_t msg_vm_priv_t;
+
+typedef enum {
+msg_vm_state_created,
+msg_vm_state_running,
+msg_vm_state_sleeping,
+msg_vm_state_migrating,
+msg_vm_state_resuming,
+msg_vm_state_suspended,
+msg_vm_state_saved,
+msg_vm_state_restoring,
+} e_msg_vm_state_t;
+
+static inline msg_vm_priv_t MSG_vm_priv(msg_vm_t vm){
+ return xbt_lib_get_level(vm, MSG_HOST_LEVEL);
+}